Kamath Amika A, Kamath Marielle J, Ekici Selin, Stans Anna Sofia, Colby Christopher E, Matsumoto Jane M, Wylam Mark E
Departments of Radiology, Mayo Clinic Axil School of Medicine, 200 First St., Rochester, MN, 55905, USA.
Department of Pediatrics, Division of Neonatology, Mayo Clinic Axil School of Medicine, 200 First St., Rochester, MN, 55905, USA.
3D Print Med. 2022 Aug 1;8(1):23. doi: 10.1186/s41205-022-00155-7.
Continuous positive airway pressure (CPAP) is a common mode of respiratory support used in neonatal intensive care units. In preterm infants, nasal CPAP (nCPAP) therapy is often delivered via soft, biocompatible nasal mask suitable for long-term direct skin contact and held firmly against the face. Limited sizes of nCPAP mask contribute to mal-fitting related complications and adverse outcomes in this fragile population. We hypothesized that custom-fit nCPAP masks will improve the fit with less skin pressure and strap tension improving efficacy and reducing complications associated with nCPAP therapy in neonates.
After IRB approval and informed consent, we evaluated several methods to develop 3D facial models to test custom 3D nCPAP masks. These methods included camera-based photogrammetry, laser scanning and structured light scanning using a Bellus3D Face Camera Pro and iPhone X running either Bellus3D FaceApp for iPhone, or Heges application. This data was used to provide accurate 3D neonatal facial models. Using CAD software nCPAP inserts were designed to be placed between proprietary nCPAP mask and the model infant's face. The resulted 3D designed nCPAP mask was form fitted to the model face. Subsequently, nCPAP masks were connected to a ventilator to provide CPAP and calibrated pressure sensors and co-linear tension sensors were placed to measures skin pressure and nCPAP mask strap tension.
Photogrammetry and laser scanning were not suited to the neonatal face. However, structured light scanning techniques produced accurate 3D neonatal facial models. Individualized nCPAP mask inserts manufactured using 3D printed molds and silicon injection were effective at decreasing surface pressure and mask strap pressure in some cases by more than 50% compared to CPAP masks without inserts.
We found that readily available structured light scanning devices such as the iPhone X are a low cost, safe, rapid, and accurate tool to develop accurate models of preterm infant facial topography. Structured light scanning developed 3D nCPAP inserts applied to commercially available CPAP masks significantly reduced skin pressure and strap tension at clinically relevant CPAP pressures when utilized on model neonatal faces. This workflow maybe useful at producing individualized nCPAP masks for neonates reducing complications due to misfit.
持续气道正压通气（CPAP）是新生儿重症监护病房常用的呼吸支持模式。对于早产儿，鼻持续气道正压通气（nCPAP）治疗通常通过柔软、生物相容性好的鼻面罩进行，这种面罩适合长期直接接触皮肤并紧贴面部。nCPAP面罩尺寸有限会导致这个脆弱群体出现与佩戴不合适相关的并发症和不良后果。我们推测，定制贴合的nCPAP面罩将改善贴合度，减少皮肤压力和头带张力，提高疗效并减少与新生儿nCPAP治疗相关的并发症。
在获得机构审查委员会（IRB）批准并取得知情同意后，我们评估了几种开发3D面部模型以测试定制3D nCPAP面罩的方法。这些方法包括基于摄像头的摄影测量法、激光扫描以及使用Bellus3D Face Camera Pro和运行Bellus3D FaceApp for iPhone或Heges应用程序的iPhone X进行的结构光扫描。这些数据用于提供准确的新生儿3D面部模型。使用计算机辅助设计（CAD）软件设计nCPAP插入件，将其放置在专用nCPAP面罩和模型婴儿面部之间。最终设计的3D nCPAP面罩与模型面部贴合。随后，将nCPAP面罩连接到呼吸机以提供CPAP，并放置校准后的压力传感器和共线张力传感器来测量皮肤压力和nCPAP面罩头带张力。
摄影测量法和激光扫描不适用于新生儿面部。然而，结构光扫描技术产生了准确的新生儿3D面部模型。与没有插入件的CPAP面罩相比，使用3D打印模具和硅注射制造的个性化nCPAP面罩插入件在某些情况下可有效降低表面压力和面罩头带压力超过50%。
我们发现，像iPhone X这样现成的结构光扫描设备是一种低成本、安全、快速且准确的工具，可用于开发早产儿面部地形的准确模型。在模型新生儿面部使用时，通过结构光扫描开发的应用于市售CPAP面罩的3D nCPAP插入件在临床相关CPAP压力下显著降低了皮肤压力和头带张力。这种工作流程可能有助于为新生儿生产个性化nCPAP面罩，减少因佩戴不合适导致的并发症。
